Conventional methods for servicing safety relief valves typically require awkward and expensive piping fabrications or even total shutdown of the system for routine or emergency service of redundant safety relief valves. Some conventional methods require two separate penetrations into the pressure vessel connected with mechanically linked block valves. Other conventional methods incorporate three-way block valves connected to a single penetration into the pressure vessel. The three-way block valve configuration commonly results in high pressure losses. The valve selector manifold of the present disclosure overcomes the disadvantages associated with these conventional methods.
This apparatus is directed to a valve mounting manifold. It is adapted to be attached to a pressure vessel for protection of the vessel against overpressure. It is duplicate valved to enable relief devices to be installed with only a single opening into the pressure vessel thereby reducing the number of openings formed in the pressure vessel. It is axiomatic that openings cut into a pressure vessel, cause problems by increasing complexity, all at an increased cost. This device enables the number of openings cut into a pressure vessel to be reduced. It defines a pressure vessel selector manifold enabling multiple safety relief valves to be installed at a single vessel opening. The valve selector manifold of this disclosure enables one safety valve to be placed in service while a second valve is out of service or even dismounted for maintenance.
The dual active valve selector manifold of this disclosure provides dual connections for relief during flowing conditions. This manifold has smoothly faired flow paths to the selected relief valves and thereby enables the relief valves to be exposed to the pressure of the vessel with minimum pressure loss during flowing conditions.
Pressure vessels typically require one or more safety relief valves for protection of the vessel in the event of overpressure. The selector valve manifold of this disclosure is particularly suitable for use with pressure vessels requiring two safety relief valves in operation to meet the safety standards established for the pressure vessel. The selector manifold of this disclosure is dual active, permitting both safety relief valves to be exposed to the pressure of the pressure vessel simultaneously through a single opening into the pressure vessel.
Periodic maintenance or repairs of the safety relief valves will be required. The valve selector manifold of this disclosure enables field servicing of one relief valve without defeating safety valve protection of the pressure vessel by the second relief valve. For instance, this device mounts duplicate safety relief valves, enabling one to be switched out of service while the other remains operative. Removal of one can be undertaken while the other is operative. This can be accomplished without reducing pressure in the pressure vessel.